Brushmaking machine and method



Aug. 3, 1954 J. G. BAUMGARTNER BRUSHMAKING MACHINE AND METHOD '7Sheets-Sheet l Filed Feb. 2. 1949 glglglgllgl MVL' Aug 3 1954 J. G.BAUMGARTNER 2,685,477

BRUSHMAKING MACHINE AND METHOD Filed Feb. 2 1949 '7 Sheets-Sheet 2JNVENTOR.

\ Aug. 3, 1954 Filed Feb. 2. 194e J. G. BAUMGARTNER A 2,685,477

BRUSHMAKING MACHINE AND METHOD 7 Sheets-Sheet 5 Aug. 3, 1954 J. G.BAUMGARTNER 2,685,477

BRUSHMAKING MACHINE AND METHOD Filed Feb.'2. 1949 '7 Sheets-Sheet 4INVENTOR.

im Eazzzgarzer BY fm m Aug. 3, 1954 J. G. BAUMGARTNER 2,685,477

BRUSHMAKING MACHINE AND METHOD Filed Feb. 2. 1949 i 7 Sheets-Sheet 5 v@l 5036)( @il IN V EN TOR.

QHWMM Aug- 3, 1954 J. G. BAUMGARTNER BRUSHMAKING MACHINE AND METHOD 7Sheets-Sheet 6 Filed Feb. 2. 1949 IN V EN TOR. Lf@ hyczwzgrzer Aug. 3,1954 J. G. BAUMGARTN'ER 2,685,477

BRUSHMAKING MACHINE AND METHOD Filed Feb. 2, 1949 7 SheebS-Sheet '7 INVEN TOR.

Patented Aug. 3, 1954 UNITED STATES ATENT OFFICE 22 claims. l

This invention relates to the manufacture of brushes, and particularlytothe manufacture of small brushes adapted for use in applying lacquerand the like.

The present application is a continuation-inpart of my pendingapplication, Serial No. 742,530, for Brush, led on April 1Q, 194'?, nowPatent No. 2,558,334 issued June 26, 1951.

Brushes now commonly used in applying lacquer, such as for applyingfingernail polish and for use in art Work, include a small cylindricalhandle into which are secured bristles normally made of pony or camelhair or other natural ber. Such natural hairs' and fibers, in theirnative condition, are not uniform in size and shape, and to provide abrush of high quality careful selection of the bers is necessary. Thisrequires a large amount of labor, making the brush relatively expensive.Failure to properly select the bristles results in a brush in which thebristles become tangled and matted, and the lacquer or other materialbeing applied is unevenly spread, leaving ridges and lines.

Bristles made of synthetic fibers such as nylon have a high degree ofuniformity and can be produced very inexpensively. Prior attempts to usesynthetic bristles in brushes have been un-v satisfactory, however, duelargely to the fact that when the bristles are cut off to uniformlengths, the ends thereof tend to enlarge or become mushroomed. Theenlarged ends of the bristles prevent the lacquer or other coatingmaterial from being applied smoothly, so that the result issubstantially no better than that obtained when poorly selected orunselected natural fibers are used.

An object of the present invention is to provide an improved machine forthe production of small inexpensive brushes having synthetic bristles.whereby the quality of these brushes compares favorably with that ofbrushes using the best grade of natural bristles.

Another object is to provide an improved method of making a small brushwith synthetic bristles having the characteristics required for smoothlyspreading lacquer or similar coating material.

A further object is to provide novel means adapted to form pointed ortapered ends on the bristles after they are trimmed, so that the lacquerhows smoothly from the bristles without clogging or matting them, and astill further object is to insure that all of the bristles in the tuftare thoroughly finished.

As a feature of the invention I have made provisions for tapering theends of the bristles to conical points by passing the bristles of anassembled brush in a particular manner across the face of a rotatinggrinding wheel.

Another feature is the use of oscillatory means for intermittentlyrotating the brushes in the course of their passage across the grindingwheel, so that all sides of the tuft are brought into contact with thewheel.

Still another feature is a unique arrangement whereby the ends of theindividual bristles in each tuft are spread out on the face of thegrinding wheel to insure their intimate contact therewith, sucharrangement including means to flatten each bristle tuft momentarilyWhile it is engaged with the grinding wheel.

rihe foregoing and other objects, features and advantages of theinvention will be better understood from a study of the followingdescription taken in conjunction with the accompanying drawings,wherein:

Fig. 1 is a front view of a machine for grinding the bristles of abrush, such machine embodying the principles of the invention;

Fig. 2 is a top view of the machine of Fig. l;

Fig. 3 is a sectional view along the line 3 3 of Fig. l;

Fig. 3a is a fragmentary elevational view along the line 3ft-3a of Fig.3.

Fig. l is an enlarged longitudinal sectional View of a rcomplete brushassembly in which there is included a brush made in accordance with theprinciples of the invention;

Fig. 5 is an enlarged View showing the natural configuration of the endsof the bristles when cut;

Fig. 6 is an enlarged view showing the conguration of the bristles afterbeing ground;

Fig. 7 is a fragmentary plan view of a second embodiment of the presentinvention;

Fig. 8 is a perspective View of the complete machine in which the secondembodiment is ineluded;

Fig. 9 is a partial front elevation showing the conveyor means of thesecond embodiment;

Fig. l0 is an enlarged view of a portion of the -conveyor and partsassociated therewith;

Fig. l1 is a plan View of they bristle finishing apparatus;

Fig. l2 is a vertical section on the line i2-l2 of Fig. 11;

Fig. 13 is a vertical section on the line Ill-i3 of Fig. 11; and

Fig. 14 is a partial perspective view of the brush finishing apparatus.

In practicing the invention, the brushes are placed on a conveyor chainwhich moves stepby-step past a cylindrical grinding wheel in a directionparallel to the axis thereof. The brushes are disposed with their`handles extending transversely of the chain and with the ends of theirbristles contacting the grinding wheel. As the brushes are moved instep-by-step fashion across the face or" the grinding wheel, they cometo rest a number of times while' they engage the rotating wheel.Oscillatory means are provided to produce rotation of the brushes asthey progress across the grinding wheel. In one ernbodiment of theinvention, the brushes are rotated between steps, and in anotherembodiment the brushes are rotated while they are at rest. The brushrotating mechanism includes a pair of gripping members that extend alongthe path of movement of the brushes. Cyclic motion is imparted to one orboth of these members for are clamped in such a way that the ends of thebristles are spread out fiat against the grinding wheel.

Referring briefly to the form of brush assembly illustrated in Fig. e,which is typical of those produced, by the use of my invention, thebrush proper includes a handle ill which may be made of any suitableplastic material with a tuit of bristles il secured in one end thereof.A finger gripping portion i2 is secured to the other end of the handlelil, and customarily this nger gripping portion i2 serves as a cap for asmall container of the type in which nail lacquer or other liquid to beapplied by the brush is kept. The handle ill has an enlarged headportionA in?. adapted to be tightly secured in a tubular projection i onthe finger gripping portion i2. The finger gripping portion may includethreads l for engaging similar threads on the container, and a sealingwasher il so that a tight seal can be made thereby. The bottom end oi'the handle l@ has a cavity i8 which extends axially within the handle toa depth at least equal to the diameter of the handle. The bristle tuit ll is received within the cavity i3 and is secured directly to the handleIll by a staple i9 straddling the bristles in the tuit for anchoring thetuit at the bottom of the cavity. lThis manner of securing the bristlesin the brush is covered in my prior Patent No. 2,438,515. Theillustrated brush as* sembly is drawn on a large scale in Fig. 4.Actually, the handle lo is about 1/8 or" an inch in diameter, and thetuit of bristles il is of the order of g3g inch in diameter. The overalllength of the handle lil and tuft El is about two inches.

The bristle tuft Ii is composed of a plurality of bristles 2| which aredoubled back about the loop formed by the staple le, as illustrated inFig. 4. The bristles are made of a synthetic liber, such as nylon, andare o a uniform diameter, about .O04 of an inch. The tutt nts tightlywithin the cavity i3 and is positioned in the cavity to such a depththat a relatively tight tuft of bristles is formed. While nylon bershave been found to be satisfactory for a nail thereof.

4 polish brush, rayon or other synthetic bers may be more suitable inother applications.

After the bers are formed into a tuft and secured in the handle asillustrated in Fig. 4, the tuft must be finished in order to provide abrush which is suitable for applying lacquer or the like. The ends ofthe bers are cut oli squarely to form an even end of the tut. It hasbeen found that when the nylon fibers are cut off the ends thereof areenlarged or become mushroomed as is illustrated in Fig. 5. Fig. 5 wasmade from a microscopic photograph of fibers approximatelyfour-thousandths of an inch in diameter, the enlarger ends'beingillustrated at 22.

Although the tuft of bristles after having the ends thereof trimmedforms a brush having an even edge, it is apparent that the enlarged endsof the bristles will not permit lacquer or similar material to be spreadsmoothly as is required in the application of iingernail polish or as isrequired in artwork or other application. It has been found, however,that ii the nylon bristles are ground to provide ends which are ofgenerally pointed configuration with a long taper, a brush having suchbristles Works very satisfactorily,

being generally superior to high class pony or camel hair brushes. Fig.6 is a greatly enlarged representation of the bristles, being taken froman actual microscopic photograph of bristles as shown in Fig. 5 afterhaving the ends thereof ground. The grinding operation may be performedby moving the end of the tuft of an assembled brush over the face of arotary grinding wheel. Fig. 6 illustrates bristles which have beenground to provide a taper of approximately 15 to l on the ends thereof.That is, the length of the taper is approximately 15 times as great asthe diameter of the bristles since the bristles taper to a point.Bristles having a taper ofk 8 to 1 have been found to be satisfactoryfor a lacquer brush, but a longer taper is preferable. In addition toproviding generally pointed ends on the bers to provide a brush whichwill spread lacquer evenly, the grinding of the ends tends to roughenthe surface of the fibers providing recesses which help to hold thelacquer on the bristles.

In Figs. 1, 2 and 3 there is illustrated one embodiment of the inventionwhich is suitable for grinding the bristles of a brush to provide ataper thereon as previously described. In Fig. 1 there is illustrated acontinuous chain 25 sup ported by four sprocket wheels 26 so that thechain can move in the manner of a conveyor. The chain includes aplurality of pivotally connected links 21 each of which has a groove 28therein adapted to receive the handle l0 of a brush. After the bristletuft H is stapled to the handle I of the brush and the ends of thebristles are cut straight across the tuft to make the bristles uniformin length, the assembled brushes are placed in the grooves 28 in thechain 25. In the apparatus shown in Figs. 1, 2 and 3, the chain isadapted to move in a counterclockwise direction so that the brushes willbe inserted in the grooves 28 at the left-hand side of the top portionthereoi as shown in Fig. l. A stationary guard 2S is provided around thesides and bottom of the moving chain to hold the brushes in position inthe grooves 28 in the chain. As illustrated in Fig. 2, as the brushesare moved along the bottom side of the guard by the chain 25, thebristle tufts are passed along the surface of a grinding wheel 3B and ina direction axially The grinding wheel is mounted on a shaft 3l which issupported for rotation by frame members 32 and 33. The shaft 3| isdriven at constant speed by any suitable means, pulleys 34 driven byV-belts 35 being illustrated by way of example.

For the purpose of turning the brushes as the bristle tufts pass alongthe grinding wheel, so as to taper the ends of the bristles, a mechanismfor rotating the handles of the brushes is provided. rThis mechanism issupported by a frame plate 4B which includes bearings for four shafts 4l42, 43 and 44. As is apparent from Fig. 1 the shaft 42 includes asprocket wheel 45 thereon which is driven by a chain 4B. Each of theshafts includes toothed gears 41 thereon which mesh with a large gear 48also supported for rotation by frame plate 45. 'Through the medium ofthe large gear 48 and the gears 41 the movement of shaft 42 istransmitted to the shafts 4i, 43 and 44, and as indicated by arrows inFigs. 1 and 3a, each of these shafts are adapted to rotate in aclockwise direction. The shafts 4I, 42, 43 and 44 have pins 5l, 52, 53and 54, respectively, at the ends thereof, the pins being of smallerdiameter than the shafts themselves and being positioned eccentricallywith respect to the shafts. A pair of gripping members 55 and 56 aresupported by the pins 5l to 54, inclusive, the gripping membersincluding vertically extending slots 51 in which the pins are received.Washers 62 are secured to the ends of the pins 5| to 54, inclusive, tohold the gripping members 55 and 55 thereon. rThe gripping members 55and 55 are further supported by springs 58 and 59 which are supported byportions 60 and 5| secured to the frame plate 40. The lower grippingmember 56 has a serrated top edge 63 as is indicated in Fig. 1. The topgripping member 55 has a resilient insert 64 in the bottom edge thereofas is clearly shown in Fig. 3. The members 55 and 55 are adapted to gripthe enlarged portions i4 of the brush handles I5 as illustrated in Fig.3 and as will be more fully described.

The chain 4 5 for driving the turning mechanism is driven by a sprocketwheel 55 secured to shaft 65 which may be driven at a constant speed byany suitable means. For driving the conveyor chain from the shaft 66,crank 51 is secured to the end of the shaft. Movement of the crank istransmitted to the conveyor chain by the use of a toothed driving wheel6B which is connected to one of the sprocket wheels 26 and a ratchetmechanism for driving the wheel 68 in accordance with movement of crank61. This ratchet mechanism includes arm (i9l (Figs. l and 3) pivotallyconnected to the crank 61, arm l@ which is pivotally connected to arm 55and which supports finger 1|, and spring 12 which holds finger 1Iagainst the teeth of the wheel 68.

Considering now the operation of the mechanism for turning the brushes,it is apparent that as the shafts 4i to 44 are simultaneously rotatedthe pins 5l to 54 eccentrically positioned thereon will describe acircle. The top gripping member 55 positioned on the pins 5l and 53 willvbe oscillatled to the right and left. The springs 58 together with theweight of the gripping member 55 will cause the member to be normallyheld in a downward position. Similarly the gripping member 55 will bemade to oscillate to the right and left due to the rotary movement ofthe pins 5i and 54, the springs 59 tending to hold the member 56 in itsup-most position. However, the slots 51 in the gripping member 55 arenot sufficiently long to absorb all of the vertical movement of theeccentrically positioned pins so that when the pins 5I and 53 are intheir highest position they will engage the top of the slots 51 in themember 55 to cause the gripping member 55 to be raised slightly so thatthe resilient insert 54 thereof will be lifted off of the brush handles.At the same instant the pins 52 and 54 will engage the bottoms of theslots 51 in the gripping member 55 to cause the member 56 to bewithdrawn from the underside of the brush handles. in Fig. 1 the pins 5Ito 54 are shown in the position in which the gripping members 55 and 55are held away from the brush handles. Figs. 3 and 3a show the grippingmembers engaging the portions i4 of the brush handles.

The common driving mechanism for the turning mechanism and for theconveyor chain 25 comprising the sprocket wheel 55 and the crank 51which are driven by the same shaft (65) permits the movement of theconveyor chain 25 to be timed so that each brush is moved from oneposition to the next position while the gripping members 55 and 55 arereleased therefrom. The action of the ratchet mechanism is such that themovement of the chain 25, will be a step-by-step process and eachmovement will be accomplished in a very short time so that the chainwill be stationary a large portion of the time. This, therefore, permitsthe gripping members to be released from the brush handle for only avery short period of time so that during substantially the entire timethat the brushes are passed over the grinding wheel 55 the handles arebeing turned.

The turning of the handles of the brushes, with the resulting change ofposition of the bristle tufts on the grinding wheel, will cause allsides of the tuft to be acted upon by the grinding wheel. rThe tuft,while being ground, contacts the grinding wheel 55 at an angle, asillustrated in Fig. 3.

A projecting ridge 13 is provided on the plate 4i) against which theends of the handles Ill rest so that the bristle tufts will be properlypositioned with respect to the Wheel. The bristles are slightly spreadas shown in Fig. 2, when they contact the grinding wheel. It is obviousthat the character of the grinding wheel used, the speed of operation ofthe grinding wheel, and the position and movement of the bristle tuftwith respeet to the grinding wheel will all affect the taper obtained onthe bristles.

The apparatus illustrated in Figs. 1, 2 and 3 produces conical tapers onthe bristles which contact the grinding wheel. To insure that all of thebristles in each tuft are brought into contact with the grinding wheel,resort may be had to the embodiment of the invention illustrated inFigs. '7 to 14. In this embodiment, as in the rst embodiment, thebrushes are moved step-by-step axially across the face of a grindingWheel Bil, but in the present instance they are rotated only while theyare moving laterally. Each time the brushes come to rest while they arein grinding position, a spreader element 82 clamps down upon the tuftsof the brushes and causes the tufts to be momentarily flattenedhorizontally so that the bristles are spread out sideways. The effect ofthis is illustrated in Fig. 7, where the bristles 2l of a tuft Il areshown fanned out on the face of the grinding wheel 35, with eachindividual bristle being brought into contact with the wheel. Theabove-described steps of rotating the brushes and spreading the bristlesare repeated alternately several times as each brush progresses acrossthe wheel. This insures that each bristle in the tuft is thoroughlyground to a conical point as shown in Fig. 6, and this is accomplishedwithout any permanent deformation of the tufts.

Referring now to Fig. 8, which is a general View of the modied machine,a supply of brush handles i is kept in a handle magazine 84. The handlesare placed by hand into a guideway 5S from which they are fed insuccession to a conveyor chain 88 that carries the brushes in ahorizontal path from one side of the machine to the other. Bristles arekept in a bristle magazine 98 from which they are fed downwardly bygravity. A tuft forming and stapling mechanism generally designated 92intermittently withdraws tufts of bristles from the magazine Si) andstaples these tufts into the handles of the brushes which have beencarried by the chain 88 into the stapling position. A suitable tuftforming and stapling mechanism which may be used in the present machineis disclosed in detail in my pending application, Serial No. 480,354,led on March 24, i943. After being stapled into a brush handle, the endsof each tuft are trimmed automatically before the brush advances to thegrinding wheel 85. The brushes are carried by the chain 88 across theface of the grinding wheel 88, and the finished brushes (that is, thehandle and tuftl combinations as iG-H illustrated in Fig. 4) are fed toa brush magazine 9d from which they are removed by hand and packed intoboxes.

Referring now to Figs. S and 9, brush handles lil are taken from thehandle magazine 8!! by hand and are placed in the guideway 85 in side byside relation. A spring-urged, pivoted presser arm 85, Fig. 8, works ina curved portion of the guideway 85 for urging the handles |5 toward adelivery point at the end of the guideway 86 directly above the left endof the chain 88, Fig. 9. There the foremost handle 18 comes to rest on ayieldable support 58 which normally is urged by a spring 58 into ahorizontal position. A stationary structure lill aiords a verticalguideway S52 extending from beneath the support 33 to the chain 8S. Aslide |54 is mounted for vertical reciprocatory movement in thestructure A rocker |56 operated by a cam |88, Fig. 9, periodicallylowers and raises the slide |54. Each 'ime the slide |84 descends, itpushes the foremost brush handle it from the guideway 85 down onto thechain 83. The support 98 yields to permit passage 0f the handle i8through the guideway |92. As shown best in Fig. l0, each link of thechain is recessed, as indicated at H5, to receive and support a brushhandle I5. The operation o the slide |55 is timed so that a handle I8 isdeposited on each pair of links in the chain 88.

The chain 88 passes around sprocket wheels as H2, Fig. 9, and thehorizontal upper pass of the chain 88 slides along a chain guidewayprovided on the upper edge portion of a block or frame H4 that extendsfrom one side of the machine to the other. A series of three pusherpawls IIS, Figs. 9 and l2, mounted on the upper ends of rocker arms ||8cooperates with the underside of the chain 88. A stationary,horizontally extending bar |20 disposed above the chain 88 serves tomaintain the brush handles i5 seated in the recesses H8 in the chainlinks and prevents upward displacement of the chain 83. The rockers H8are actuated in unison by a cam |22, being oscillated back and forth toimpart intermittent step-by-st-ep movement to the chain 88. Thus, thebrush handles it! are carried by the chain 88 to the stapling positionwhere the bristle tufts are secured thereto, thence to the grindingposition where the bristles are 8 iinished, and nally the finishedbrushes are stripped from the chain 88 and are deposited in the brushmagazine 85, Fig. 8. A weighted lever |24 prevents the brushes fromspilling back out oi the magazine Sli onto the chain 88.

The brush handles i0 project a substantial distance beyond the frontedges of the chain 88 and guide block H4. Alpivoted sensing finger |28,Fig. 9, rests at its lower end upon these projecting portions of thehandles I8 that are being carried by the chain 88. The lower end of theiinger |28 is of sufiicient length horizontally so that the finger |25is maintained in an elevated position so long as there are brush handlesE8 on the chain 88. if the supply of brush handles in the guidewayshould become exhausted, so that no more brush handles I8 are carried bythe chain 88, the finger |26 drops by gravity and causes a switch E28controlled thereby to close. rihis completes a circuit to a suitableWarning device such as a lamp or buzzer, advising the operator that theguideway 36 is empty.

A supply of synthetic bristles may be placed on the tray |38, Fig. 8, atthe front of the machine. The operator passes the bristles through astationary comb |32 and then places them in the bristle magazine 85.From the magazine 89 the bristles are fed by gravity to the tuft-formingand stapling mechanism 82, which secures the bristles to the brushhandles i8 carried by the chain 88. Then the brushes are carried by thechain 88 in step-by-step fashion across the face of a cylindricalgrinding wheel 8!) as indicated in Fig. ll. A guide strip i3d, Figs. ll,12, 13 and i4, cooperates with the head portions il! of the brushhandles l5 to hold the brushes with their bristle tufts engaging theface of the grinding wheel 88. The axial length of the grinding wheel 38is suflicient to accommodate a large number of brushes. The brushes arecarried step-by-step axially across the grinding wheel 85 by the chainF38, and each brush comes to rest a number of times while cooperatingwith the wheel 85.

A bracket |35, Figs. 1l and 14, supports a set of |39 and |135 which areconstantly driven. The gears |38 and |40 are mounted on shafts M2 and|53 which extend through bearings and supported by the bracket |36rearwardly of this bracket. The shafts |42 and 43 terminate in cranks|66 from which crank pins |48 extend through vertical slots |55 in anoscillatory gripping member |52, as best shown in Figs. l2 and 13. Thegripping member |52, consists of a bar |54 (in which the slots |50 arelocated) and a resilient insert |56 in the lower edge portion of the bar|55. The gripping member |52 is positioned above the enlarged headportions Iii of the brush handles l5. Beneath the head portions le thereis disposed a stationary gripping member or bar |58 having a serratedupper edge, as shown in Figs. ll and 14. This serrated upper edge ispositioned to engage the handle heads |13 from beneath.

The gripping member |52 is supported by the crank pins |48. A weight |58on the bar |54 tends to urge the upper gripping member 52 intoengagement with the brush handles I9, rI'he slots |55 in the bar |54 areof such character that when the crank pins |48 are in their upperpositions, the gripping member |52 is lifted clear of the brush handlesi8. As the crank pins |48 descend, the gripping member |52 is shifted toone side and the crank pins |133 enter the lower portions of the slots|58 where there is a certain .tangential-ly across the brush handles.

amount of vertical lost motion. The gripping member |52, after beingbrought to bear up on the heads I4 of the brush handles I0, is movedThis causes the brush handles to be rotated on the chain 83 for turningthe bristle tufts I of the brushes which are engaged with the grindingwheel 80.

Normally the oscillatory mechanism for rotating the brush handles iscovered by a guard |62, Fig. 8, which is shown swung open in this view.The timing of the parts is such that the brush handles are rotated onlyWhile the chain 88 is in motion, the purpose of this arrangement beingexplained presently. Notches |64 in the upper edge of the stationaryhold-down bar |20, Figs. l1, 13, and 14, aiord clearance for the crankpins |48. A guard |66, Fig. S, encloses the gear mechanism for operatingthe rotative parts.

When the brushes come to rest intermediate their successive steps ofmovement, the bristle spreading means becomes effective. As shown inFigs. 11, 13 and 14, the bristle tufts project over a ledge |68 formedon an extension of the block or frame H4. This ledge |63 is locatedclose to the face of the grinding wheel 80 approximately 2/3 of thedistance back from the ends of the bristle tufts Directly above theledge |68 is located the spreader element 82, which comprises a ila-tbar positioned vertically and extending parallel to the axis of thegrinding wheel 8|). The spreader bar 82 is carried by rocker arms |10that are mounted on a small shaft |12 journaled in bearings on the upperend of the bracket |35. A rocker |14, Fig. 11, extending from the shaft|12 is actuated by suitable linkage means- |15 (Fig. 8) forintermittently rocking the shaft |12. This causes the arms |10 carryingthe spreader bar 82 to be rocked up and down.

While the brushes are at rest, the spreader bar 82 moves down to clampand flatten the portions of the bristle tufts disposed on the ledge |68.This causes the bristles 2| in each tuft Il to be spread out laterallyso that the individual bristles lie flat against the face of thegrinding wheel Bil. In other words, the bristles 2| are caused to fanout as shown in Fig. '7.

As the brushes pass across the face of the grinding wheel 80, beingalternately subjected to rotating and bristle-spreading operations, theends of the bristles are ground to uniform conical points. Uniformtapering of the bristles is assured by these spreading and rotatingoperations, whereby the individual bristles are made to engage thegrinding wheel for equal periods of time. Thus, it will be seen that themachine produces a brush having synthetic bristles which is far superiorto brushes of this type produced by prior machines and methods. Thebrushes are much cheaper in price and are equal in quality to brushesmade with the best selection of natural bers.

The illustrated embodiments of the invention exemplify the manner inwhich the principles of the invention may be applied. Other embodimentscoming within the scope of the present teachings are possible, and it isintended that such modications shall be included within the spirit ofthe appended claims.

I claim:

l. In the manufacture of a brush having a tuft of synthetic bristlesextending from a handle, the method of tapering the ends of the bristleswhich comprises the steps of holding the brush l0 by its handle with theend portions of the bristles engaging a rotating grinding wheel, andmomentarily iiattening the portion of the tuft intermediate the handleand the ends of the bristles for spreading the bristle ends flat againstthe face of the grinding wheel.

2. In a machine for producing brushes each having a tuft of bristlesextending from a handle, apparatus for finishing the ends of thebristles comprising in combination a grinding wheel, a conveyor spacedfrom said grinding wheel adapted for carrying brushes into cooperationwith said wheel, said conveyor having provisions for supporting eachbrush with the bristle tuft extending into Contact with the face of saidwheel and the brush handle extending away from said wheel, meanssupporting and driving said conveyor in said apparatus, a pair ofrelatively movable brush handle gripping members mounted adjacent saidconveyor, cyclicaily operable actuating means operatively connected withone of said gripping members for producing relative oscillatory movementof said gripping member toward and away from the other and angularlywith respect to the conveyor which would be tangentially relative to anybrush handles on the conveyor thereby to rotate each brush handleintermittently while the bristles are being ground, relatively movablespreader members and means for supporting the same for a relativemovement of one member with respect to the other in a space between saidgrinding wheel and said conveyor and adapted for engagement withopposite sides of the bristle tuft of a brush, and reciprocatoryactuating means operatively connected with said one spreader member forproducing relative movement of said spreader member toward and from theother.

3. In a machine for securing bristle tufts to brush handles, thecombination of a handle delivery guideway, a horizontally extendingconveyor chain having longitudinally spaced recesses therein forindividually receiving brush hande intermittently operable actuatingmeans operatively connected to said conveyor chain for impartingstep-by-step movement thereby, means adapted to bear on brush handles insaid guideway for feeding brush handles in succession to a predetermineddelivery position above said chain, a yieldable support means forholding each brush disposed in such delivery position, and a verticallyreciprocable slide operable in timed relation with the movement of saidchain for moving the brush handles successively from said yieldablesupport through said guideway to be deposited on said chain.

4. The method of tapering the end portion of synthetic bristles for abrush to provide a pointed tapered configuration on each bristle, suchmethod comprising the steps of holding the bristles adjacent the endportions thereof to maintain such end portions spread on the rotatingsurface of a grinding wheel, grinding the bristle end portions to grindone side of each end portion, releasing the bristles, rotating thebristles to present another side of the end portion of each bristle tothe rotating surface of the grinding wheel, and alternatively repeatingthe steps of holding, grinding, releasing, and rotating the bristleswhile intermittently moving the same in a line of travel relative to thegrinding wheel.

5. The method of tapering the end portions of bristles for a brush toprovide a pointed tapered configuration on each bristle, such methodcomprising the steps of clamping the tuft of bristles adjacent the endportions of the bristles in the tuft to spread out the bristles fanwiseand to maintain such end portions spread on the rotating surface of agrinding wheel, grinding the bristle end portions thereby, releasing thebristles from the clamping, rotating the tuft of bristles to presentanother side of the end portion of each bristle to the rotating surfaceof the grinding wheel, and simultaneously moving the bristles along apath of tra-vel relative to the grinding wheel, and alternativelyrepeating the steps of holding, grinding, releasing, and rotating thebristles while intermittently moving the same.

6. In the manufacture of a brush having a tuft of bristles and a handlewith the bristles extending longitudinally from the end of the handle,the method of grinding the outer end portions of the bristles intoconical tapers which comprises conveying a plurality of such brushesrelative to a. moving abrasive surfacey applying the end portions of thebristles thereof in a fanwise pattern to grind such end portions on themoving abrasive surface, rotating each conveyed brush at the handle torotate it completely around during an entire grinding operation andsimultaneously rotating the bristle tuft therewith to present the endportions of the bristles to the abrasive surface in differentcircumferential positions so that during the complete grinding operationeach bristle tuft is turned completely and the bristles ground in aconical taper at the end portions on the moving abrasive surface.

7. The method of tapering by grinding the end portions of the bristlesin the handle of a brush, which comprises supporting a plurality ofbrushes at the handles on a moving conveyor, applying the end portionsof the bristles to a moving abrasive surface while conveying the brushesrelative to the moving abrasive surface, spreading the end portions ofthe bristles fanwise on the moving abrasive surface and grinding suchend portions while so spread fanwise, and rotating the brushes during agrinding operation so as to bring all sides of the end portions of thebristles into engagement with the abrasive surface and thereby grind. aconical taper on such end portions.

8. rr the manufacture of a brush with a handle having a tuft of bristlesextending longitudinally from the end of the handle, the method ofgrinding the outer end portions of the bristles into conical taperswhich comprises conveying a plurality of such brushes relative to amoving abrasive surface with the end portions of the bristles thereof inengagement with the moving abrasive surface, clamping the bristles ofeach conveyedbrush between the ends thereof, spreading the end portionsof the bristles fanwise against the moving abrasive surface, rotatingeach brush being conveyed, and continuing to intermittently clamp thebristles and continuing to rotate the brushes so that during thecomplete grinding operation the bristles are engaged on all sides at theend portions by the moving abrasive surface.

9. A machine for producing a brush having a handle with a tuft ofconically pointed bristles extending therefrom, said machine includingin combination :abrasive-surfaced means movably supported in themachine, driven conveyor means for supporting brushes thereon mounted tomove adjacent said abrasive-surfaced means and relative thereto, brushhandle engaging-means including a oar mounted adjacent the path ofmovement of said conveyor means, means operating lll said engaging meansand said conveyor means in timed relation and means mounting said barand moving said bar in an oscillatory path and intermittently into andout of engagement with tbe conveyed brush handles to rotate the same, abristle tuft spreader member in the machine spa-ced laterally from theconveyor in the direction of the abrasive surfaced means, and meansconnected to said member to raise and lower the same in timed relationto the engaging means.

10. A machine for continuously grinding the bristle ends of the bristletufts of a plurality of unitary brush handle and bristle tuft workpiecesa-nd comprising a movable abrasive surface adapted to simultaneouslyreceive in grinding engagement the bristle ends of a plurality of saidworkpieces, means to move said abrasive surface, conveyor means movablerelative to said abrasive surface and adapted to simultaneously convey aplurality of said worlrpieces parallel thereto, means to intermittentlymove said conveyor means, guide means positioned parallel to saidconveyor means and adapted to continuously constrain said worlrpiecestowards said surface in a manner to flex the bristle ends of saidworkpieces into grinding engagement with said abrasive surface duringthe passage of said workpieces parallel to said abrasive surface,gripping means operative to intermittently grip and rotate saidworkpiece-S to rotate the bristle ends during their engagement with saidabrasive surface and timed to be operated when said conveyor means ismoving, and means operative to engage and spread said bristle ends intofanwise engagement with said surface and timed to be operated when saidconveyor means is not moving, said gripping means including a pair ofgripping bars having a length sufficient to simultaneously grip aplurality of said workpieces and positioned substantially parallel tosaid conveyor means and abrasive surface, a first one of said bars beingfixed below the plane of said conveyor, the second one of said barsbeing movably positioned above the plane of said conveyor and movabletowards the rst bar to thereby grip the plurality of workpieces betweenthe opposing surfaces of said bars, and means to osciliate said secondbar to and from said first bar with a component motion parallel to saidfixed bar during the interval when said workpieces are gripped betweensaid bars to thereby rotate said workpieces.

ll. The invention of claim l0 in which said first gripping bar includesa serrated gripping surface and said second gripping bar includes aresilient gripping surface.

l2. A machine for continuously grinding the bristle ends of the bristletufts of a pliu'ality of unitary brush handle and bristle tuftworkpieces and comprising a movable abrasive surface having a Widthtransverse to its direction of movement sufficient to simultaneouslyreceive in grinding engagement the bristle ends of a plurality of saidworkpieces, means to move said abrasive surface, conveyor means movablein one direction parallel to the width of said abrasive surface andadapted to simultaneously convey a plurality of said workpieces parallelto the width thereof, means to intermittently move said conveyor, guidemeans positioned parallel to said conveyor means and. adapted tocontinuously constrain said workpieces towards said surface in a mannerto flex the bristle ends of said workpieces into grinding engagementwith said abrasive surface during the passage of said workpiecesparallel to the width of said abrasive surface, gripping means operativeto interymittently grip and rotate said Workpieces to rotate the bristleends during their engagement with said abrasive surface, said grippingmeans including a pair of relatively movable gripping bars having alength substantially equal to the Width of said abrasive surface andpositioned substantially parallel to said conveyor means and abrasivesurface, one of said bars being positioned below the plane of saidconveyor, the other of said bars being positioned above the plane ofsaid conveyor, and means to intermittently oscillate each of said barsto and from each other with component motions parallel to said conveyorand in opposite directions during the interval when a plurality of saidWorkpieces are gripped between said bars to thereby rotate saidworkpieces.

13. A machine with a movable abrasive surface and mechanism for handlinga plurality of workpieces each of which comprises a handle with abristle tuft thereon adapted to be ground at its outer end portion bythe movable abrassive surface so as to provide a conical taper on theouter end portions of bristles in the tuft, said machine mechanismincluding in combination workpiece conveying means moving adjacent themovable abrasive surface and adapted to carry a plurality of worlzpiecesthereon with the bristle tufts thereof extended toward the movableabrasive surface, bristle tuft spreader means including a pair ofmembers, means causing relative movement in said members to clamptherebetween a bristle tuft intermediate the ends of the tuft to spreadout the same in a fan shape and maintain the outer end portions ofbristles in the tuft against the movable abrasive surface andalternately to release the bristle tuft from said clamping, meansadapted to act on the handles of the conveyed workpieces to rotate theworkpieces relative to the conveyor means and the movable abrasivesurface, and means for timing the movement of the conveyor means andsaid bristle tuft spreader means so that the conveyor means is stoppedWhile the spreader members maintain the outer end portions of bristlesin the tuft against the movable abrasive surface.

14. A machine with a movable abrasive surface and mechanism for handlinga plurality of workpieces each of which comprises a handle with abristle tuft thereon adapted to be ground at its outer end portion bythe movable abrasive surface so as to provide a conical taper on theouter end portions of bristles in the tuft, said machine mechanismincluding in combination a workpiece conveyor adjacent the movableabrasive surface to carry a plurality of Workpieces thereon with thebristle tufts extending toward the movable abrasive surface, meanssupporting and driving said workpiece conveyor in said machine, tuftspreader means including relatively movable spreader members and meansfor moving at least one of said members relative to the other to clamptherebetween a bristle tuft of a workpiece and spread out the same in afanvvise configuration with end portions of bristles in the tuft on themovable abrasive surface to be ground thereby, means adapted to act onthe handles of the Workpieces on the conveyor to rotate said handles andthereby rotate the workpieces relative to the conveyor and movableabrasive surface, and cyclical timing means in the machine actingrelative to the conveyor driving means and to the tuft spreader means tostop the conveyor means while the spreader members of said spreadermeans clamp between the same and maintain a bristle tuft spread fanwisefor grinding the end portions of bristles therein on the movableabrasive surface.

l5. In the manufacture of a small brush of the order of 2 inches inoverall length having a tuft of synthetic bristles each of whichbristles is no more than ,004 inch in diameter extending from a handleof the order of 1/8 inch in diameter, the method of tapering the outerends of synthetic bristles in the tuft which includes the steps 'ofsupporting the small brush at the handle,

clamping and flattening a portion intermediate the ends of the bristletuft from opposite sides to spread the tuft into a fanwise shape at itsend portion, grinding bristles in the tuft at the outer ends thereofWhile spread out fanvvise, releasing the tuft from the clamping,rotating the small brush to a position at which to compress, spread, andgrind another side of the bristle tuft at the end portion thereof andhence the outer ends of bristles therein, and repeating said steps fortaper grinding the outer ends of synthetic bristles in the tuft.

16. In the manufacture of a small brush having very thin and flexiblesynthetic bristles eX- tending in a tuft from a handle, the method oftapering the outer ends of synthetic bristles in the tuft which includesthe repetitive operation of performing the steps of moving the smallbrush along a path, clamping and momentarily attening the bristle tuftto spread it at its end portion into a fan, grinding the end portion ofsynthetic bristles in such tuft, releasing the bristle tuft from theclamping, and rotating the small brush sufficiently to malte anotherside of the bristle tuft available for the grinding of end portions ofsynthetic bristles therein.

17. In a machine for producing brushes which have a single compact tuftof bristles extending from a handle with the bristles being thin andindividually yieldable over the length thereof, apparatus for finishingthe outer end portions of the bristles by grinding the same, saidapparatus including in combination, moving grinding means, brushhandling means for retaining a brush in a predetermined position withthe bristles thereof extending toward the grinding means, a bristle restso constructed and so positioned relative to said brush handling meansthat a bristle tuft of a retained brush will engage said bristle rest onone side of said tuft intermediate the brush handle and the outer endsof the bristles, fanning means for acting on the other side of thebristle tuft on said bristle rest and cooperating with said bristle restto spread out the outer end portions of bristles and momentarily applyouter bristle-end-portions to the moving grind'- ing means in a fanwisepattern so that a substantial number of the bristle-end-portions in thetuft are presented to thegrinding means for grinding, said brushhandling means operating to turn a brush retained thereby to presentothei bristles to the grinding means, and means in the apparatuscooperating with said brush handling means and said tanning means forinterruptedly and repeatedly operating said two latter means tomomentarily present in the fanwise pattern different parts of thebristle tuft to said moving grinding means for grinding outerbristle-endportions into a tapered configuration.

18. In a machine for producing brushes which have a single compact tuftof bristles extending from a handle with the bristles being thin andindividually yieldable over the length thereof, and

the machine having grinding means for finishing the outer end portionsof the bristles by grinding the same, the combination includingsupporting means for retaining a brush in a predetermined position withthe bristles thereof extending toward the grinding means, a bristle restso constructed and so positioned relative to said supporting means thatthe single bristle tuft of a brush on said supporting means will engagesaid rest on one side of said tuft at a position between the brushhandle and the outer ends of the bristles, fanning means acting on theother side of the bristle tuft and cooperating with said bristle rest tospread out the outer end portions of bristles and apply outerbristle-end-portions to the moving grinding means in a fanwise pattern,means for rotating the brush at its handle where it is retained on thesupporting means, and the combination also including means cooperatingwith said rotating means and ianning means to operate said two meansalternately and interruptedly and repeatedly to correspondingly presentin such a fanwise pattern different parts of the single bristle tuft tosaid, moving grinding means to grind outer bristle-end-portions into atapered configuration by a plurality of grinding operations on the brushtuft.

19. In a machine for producing brushes which have a bristle tuft whereinthe bristles extend from a handle and are each yieldable over its lengthand the machine having apparatus for finishing outer end portions of thebristles by grinding the same, said apparatus including in combination,movable grinding means, means for supporting a brush with the bristlesextending toward the grinding means, and controllable means adapted torepeatedly and interruptedly spread out and apply the outer end portionsof the bristles of a brush against the movable grinding means in afanwise pattern, with said movable grinding means adapted to grind outerbristle-end-portions So spread thereon into tapered configurations, saidcontrollable means including means acting on opposite sides of a bristletuft at a position between the brush handle and the outer bristle endsto compress the bristle tuft at such position in a manner to spread thesame in the fanwise pattern at the outer end portions of the bristlesagainst the grinding means so that end portions of more bristles can beground on the movable grinding means than would be ground without sospreading the bristle tuft.

In a machine for producing a plurality of brushes each having a tuft ofbristles yieldable over their length and extending from a handle, andthe machine having movable grinding means for finishing the outer endportions of the bristles, the combination including means for supportinga plurality of brushes simultaneously with the bristles of eachextending toward the grinding means, and controllable means adapted torepeatedly and interruptedly spread out and apply the outer end portionsof the bristles against the movable grinding means in a fanwise patternfor only a brief interval at each time of applying with the movablegrinding means adapted to grind outer bristle-end-portions into taperedconfigurations, said controllable means including a machine portionagainst which tufts of the plurality of brushes engage and with suchmachine portion positioned relative to the movable grinding means suchthat the engagement will occur at a point between the brush handles andthe outer bristle ends thereof, and means for simultaneously acting onthe sides of all of the plurality of bristle tufts opposite to the sidesat the machine portion to simultaneously compress and spread in thefanwise pattern the outer ends of the bristle tufts so that outer endportions of more bristles can be ground on the movable grinding meansthan would be ground without so spreading the bristle tufts.

21. In the manufacture of a brush having a tuft of bristles extendingfrom a handle therefor which bristles are each readily yieldable overthe length thereof, the method or" tapering outer end portions ofbristles in the tuft which comprises the steps of presenting a brush tomoving grinding means with the bristles in the tuft extending toward thegrinding means, momentarily acting on the bristle tuft so that it isattened out from pressure applied on at least one side thereof at aposition between the handle and the outer ends of the bristles to causethe bristle-end-portions to spread fanwise, grinding outerbristle-end-portions spread fanwise on the grinding means, turning thebrush handle to present other outer bristle-end-portions in the tutt tothe grinding means, again momentarily so acting on the bristle tuft foragain spreading the outer bristle-end-portions fanwise, grinding otherouter bristle-end-portions, and repeating the steps of flattening, ofgrinding, and of turning, for the purpose of grinding to a taperedconiiguration outer end portions of bristles in the tuft.

22. n the manufacture of a brush, the method of tapering the outer endportions of yieldable synthetic bristles for a brush including the stepsof presenting a tuft of bristles toward a moving grinding means,clamping the tuft momentarily at a point between the opposite ends ofthe bristles in the tuft to compress the tuft and spread out the endportions of the bristles at the outer end of the tuft and applying thespread bristle-end-portions fanwise on the grinding means, grindingouter bristle-end-portions spread ianwise on the grinding means, turningthe tuft to present other bristle-end-portions at such outer end of thetuft to the moving grinding means, repeatedly so clamping the tuft, sogrinding bristle-end-portions, and so turning the tuft for the purposeof grinding to a tapered configuration end portions of bristles in theouter end of the tuft.

References Cited in the le of this patent UNITED STATES PATENTS NumberName Date 184,348 Dayton Nov. 14, 1876 339,361 Beers Apr. 6, 1386575,870 Beers Jan. 26, 1897 647,485 Eberling Apr. 17, 1900 845,096Malpass Feb. 19, 1907 1,365,596 King Jan. 18, 1921 1,388,403 CasellaAug, 23, 1921 1,495,747 Izawa May 27, 1924 1,684,872 Logue Sept. 18,1928 1,794,975 Mershon Mar. 3, 1931 1,888,675 Izawa Nov. 22, 19322,053,435 Kimball Sept. 8, 1936 2,229,312 Silven Jan. 21, 1941 2,365,396`Cunningham Dec. 19, 1944 2,425,438 ONeal Aug. 12, 1947 FOREIGN PATENTSNumber Country Date 287,359 Great Britain Mar. 22, 1928 503,557 GermanyJuly 25, 1930

